After the upgrade everything works except one thing - using nagrestconf inside the DSM no longer works, so you need to open nagrestconf in a new window:
http://diskstation:8888/nagrestconfIt seemed to work but I didn't test it fully. Nagios was working and logs looked okay.
Next, I uninstalled Synagios, then re-installed it again, and that didn't go too well.
It looks like synology have changed the tar options when the installer untars the files.
I'll have to fix the file permissions in the postinst script and release a new package.
Thanks the heads-up!